Bsake



oct. 19 ,1926.

B. LIEBOWITZ BRAKE Filed'Jan. 20, 1926 NGQ 2 Sheets-Sheet l Oct. 19 1926.

B. LIEBOwl-rz BRAKE Filed Jan. 20. 1926 2 Sheets-Sheet 2 ATTORNEY Patented Get.. 19, 1925.

rests BENJAMIN LIEBOWITZ, OF PENNSIDE, PENNSYLVANIA.

BRAKE.

Application filed January 20, 1926. Serial No. 82,557.

My invention relates to brakes for motorV setting and releasing, will requireV infrequent adjustment, and will not make 'heavy physical demands upon the operator in setting. These, and other objects, such as simpler ',1nechanism, improved equalization means,

improved operation, areachieved in the construction, one'form' of which is shown the i laccompanying drawings,'i n which: F y* Fig.Y lfis an elevation, partly cut away.

Fig. 3`is a view of'the'equalizing and 'eX- panding means'inneutral position. V,

Fig. 4 isY a view showing 'the same vin an intermediate position.

' Fig. 5 is a view'showingamodiiication ofK said means, and

Fig. 6 is a diagrammatic'plan view of a kmotor vehicle showing the mechanism connected with the brakes. y v

Referring to the drawings in which I have shownv a Aforni adapted to be mounted on the rear end of the transmission of a vmotor vehicle, 1 represents a fragment of motor vehicle transmission, with main shaft 2 and rear bearing 3. Fastenedto the end of the shaft in the usual way is a flanged hub 4, having studs 5 to receive a universal joint 58 of a propeller shaft 59. It will be seen that a is directly connected with the propelf ler shaft,and therefore rotates whenever the vehicle is in action. `The angeislarger in diameter, however, than the customary universal-joint-hub fiange,and carries a fricportedlon carrier "f 10 and held-thereon by` tion disc-lining 6. A. second disc 7 is farranged close to Athe Ylining6, the clearance :be-V

ing adjustable by means of bolts8. Fastened Y to disc 7 isa-two-lobedsymmetrical"earnY 9, which, together with disc 7, is rotatably supthreaded ring' 11. The inside diameter of carrier 10 islarge'enough toaiford clearance at all times between it and the hub of 4.

i. The carrier 10 has'two earsl2 formedwith mounting able. 1These twisting actions may be taken-up` pins 13 working freely in bushings 14 which are carried in the ends of arms 15 extending from the shaft 16 which shaft is carried-in bearings 17 mounted on the transmission case 1. Keyed on the end of 16 is lever 18, which is connected by rod orcable, or in any otherzsuitable manner to the brake-pedal or hand brake (not shown). The usual spring (not shown) which serves to keep the brake- .pedal in its neutral position may also serve tohhold lever 18 back, so as to press disc 7 firmly against the clearance-adjusting bolts 8. lThe disc 7 is thus held normally out of contact with lining 6 and no part of its contacts with rotating parts. lVhen, however, lever 18 is pulled forward by depressing the brake-pedal, dise 7 is brought into Contact with the lining 6, and if the vehicle is yin motion, or tends to move 7, tends to be carried around with 6, thereby rotating cam 9.

The carrier 10 has a downward extensionv 10a, which carries a pin 31 on which is pivoted the links 30. A bar 1K9 is pivoted to link 30 at.20, substantially at the mid-point ,fof bar 19. At each end of 19 is a pin 24 by means of which the pair of levers 23 are pivotally supported.` The upper ends of levers 23 carry large rollers 25 which bear against diametrically opposite points of cam 9. The lower end of each lever 23'carries a threaded eye 32.

Each of these eyes 32 is fastened to a rod 51 which connects with a bell-crank 52, mounted, for example, on the side-rail 53 of the chassis. Each bell-crank in turn is connected by a rod 54 to a lever 55 keyed to a brake actuating shaft 56, by means of which brakes 57 are set. vThe arrangement of parts 53, 54:, 5556, 57 may be varied in any conventional orv convenient manner and may be adapted for Vany number of brakes.

Referring to Fig. 4f, it will be seen that the torque react-ions set up'in the mechanism are lresisted by tensions Ain rodsf51, which are connected to the mechanism through the, eyes 32, and thereby cause a twisting action whichy rotate the line joining the eyecenters 32-,32 from the hori- 'zontaL *This'action is not disadvantageousin fact it'hasthe advantage Ofincreasing the angle'of rotation of cam 9'andthereby increasingthe energy available-unless it becomes-too large for the clearancev availcarrier 1,0. i y A `The mode of operation isk as follows:

i shown in within .the equalizing mechanism itself by doubling up pins 31 and 20 and linlrs` as tig. 5. In this case the torque reactions are taken ultimately )ins '14, thence through shaft 16 by bearing rackets 17. It will be observed that there is no longitudinal relative motion between cam 9 and rollers 25 kwhenthe brake is being set 'or released, because `in this construction, ,the cam y9 directly vand I,the rollers indirectly are mounted on the same part, nainelycam When the lvehicle `is'moving orV tends to move and the operator depresses the brakepedal (or hand-lever, as the case .may be), lever 18 is pulled forward, thereby'moving the arms 1154 `backward, and vpressing "disc 7 againstvbrke-lning.with a force'de ending on thepedal fessure.` Flange 4,' eirig directly connecte to the propel-ler shaft,`".is in motion r tends to move, so thatfdi'sc 7 tends to be rotated by flange 4. Cam `9 isA thereby rotated, ,thus forcing the V,rollers apart, causing levers 23 to rock on pivots 24 thereby drawing inward eyes ,32, which pull o n rods 51 and in turn, through bell-cranks 52 apply tension to rods 54; to operate the brakes 57. When this,alc'tin'r `has proceeded tofthe point where` all slack inthe connections and all clearances have been taken up, the brake-setting forces'acting on the eyes 32 1through the chain of` mechanism inducev a reaction between' rollers 25 and cam 4Sand prevent further retation of the latter, so that slipping thereafter occurs between disc 7 and lining 6,. It will readily be seen that the brake-,setting Aforces exerted 4by levers 23 are proportional to the pull on lever 18, Otherthings being equal, provided thatcam 19" is of constant r1se.

When the operator releases the brakepedal (or hand brake)n the pull ofthe brakeconnections on levers 23, aided by springs not shown, tends to restorey the systemfto its neutral or none-operative positie, ,by the pressure of rollers 25 against cam 'That thisy may be accomplishe ,there must be no binding forces in the mechanism, and the angle ot the cam 9 must be sufficiently large,

, are fulfilled inthe lconstruction shown.

Vwith due regard paidto diameters frollers 25 and their pivots' 24;. These' conditions It should be. observed, in 'the first place, that the forces exerted thefeyes 32 are equalizyed byvvirtue ofjtheyequalizer bar 1Q. Ifeach ofthe eyes 32 cnnected to ,rearwheel brake as in" Eis-6, 110 further equ=11-irQ11Y is necessarr *Equalization is scribed, a carries-a @am mounteatmum @veeleer Qnsaidicarrieria-pair of followers in' media Vif-tue di' action QtflinkO.-

n the second place, by virtue at this efiealiaetieli, 'ne binding farces arebreught' mtO actlon'between cam 9 and carrier 10;

WVere it not 4f orthis equalization high bearing pressures would-be induced between 9 Ya'ndnliO, and these pressures would oppose anced reaction of the two rollers 25 on they cani 9. Complete release of the brake is therefor assured by the pressure of the rollers 25 on cam 9 caused by springs not shown, especially in view ofthe Vvery liberal roller diameters and cam angle, so that'the lines of action ofthe resultant restoring forces are 4farV outsi de the ,cone of friction.

In the third place, because of the vsymmetry ofthe cam, `the brake functions `equal- '1y well, ,Whether -the vehicle is going forward or backward.`

" In the fourth Place the Cw hes a useful angle of rotation of almost .90 degrees, and is'.fundam entally because fof this large angle of was@ ,the metile here isabl to liver so muchenergy, i f

i The cam .9 is shown symmetrical, but it marieke ether ferne My invention i s showninf this specification as mounted at the rear end Aof the transmission, but itwill be understood that it may be mountd't-reithe? and lof; er at any convenient peint alergth PrOPeUer-Shaft, oran-y other shaft permanently `connected with or geared to the wheels. Furthermore the invntianism@ to be ,construed es lifnf ited to the YSpetic embodiment shown.

\ What I Claim is:

1. In combination with the-brakes and a rotating part of a motor vehicle, a mechanism for applying the brakes with equalized pressure comprising a member movable into engagement with the rotating part to rotate frictionally therewith, a camconnected with said member to* move singularly upon rotation thereof, a pair of followers each beari ing against an opposite part of the cam, and

opposite 'part ofthe. cam, anequalizing bar cennectng the followers together. andpivotallvsiipportedon the carries; and operative l connections *between the lfollowers A'and the* bralma` Y.

,i 3,111 Va mechanism ot the characterv deeach Ybearingy againstaa-:cppositepart ofthe cem-and. al; eeuahzmg baraeonnecting the followers together and linked to the Carrier..

4. In a mechanism of the character described, a cam, a pair of followers eacb. bearing against an opposite part of the earn, and pivoted equalizing means connecting the followers together.

5. In' a mechanism for applying the brakes of a motor vehicle with equalized pressure, a longitudinally movable Carrier, a earn mounted to turn angula rly on the carrier, rollers each bearing against an opposite part of the Cam, levers each carrying a roller at one end and having its other end operatively connected With one of the brakes, and an equalizing bar pivotally secured at its ends to said levers respectively, the equalizing bar being supported intermediate its ends on links pivotally secured to a part of the carrier.

BENJAMIN LIEBOVVlTZ. 

